Short answer: the WW Speaker Cabinets X21 - B&C 21DS115-4 is the proven choice, measured and ranked among subwoofers, while the newer Genelec 7370A has no independent measurements yet and can only be compared on specs.
The case for the Genelec 7370A: 12-inch (305mm) driver with a 400W Class D amplifier.
On the WW Speaker Cabinets X21 - B&C 21DS115-4 side: 21-inch driver in a large ported cabinet delivers 131.3dB CEA-2010-A average, the highest output of any passive subwoofer tested.
Price: the Genelec 7370A lists at $4,195 and the WW Speaker Cabinets X21 - B&C 21DS115-4 at $3,995.
Buy the WW Speaker Cabinets X21 - B&C 21DS115-4 if you want a speaker whose sound quality has been measured and ranked.
Buy the Genelec 7370A if you prefer its design or features, and you can wait for measurements to confirm how it sounds.
Want more options? Browse the full Subwoofers rankings.
Specifications Side By Side
| Genelec 7370A | WW Speaker Cabinets X21 - B&C 21DS115-4 | |
|---|---|---|
| Price | $4,195 | $3995 Passive |
| Ranked | - | #3 of 109 in Large Home Subwoofers (Over 75 lbs) |
| Drivers | 12” (305mm) driver | 21” (533mm) driver |
| Amplifier Power | 400W (Class D) | - |
| Frequency Response | 19Hz - 100Hz (+/-3dB) (Manufacturer specified) | - |
| Maximum SPL | 113 dB | - |
| Dimensions | 625H x 555W x 496D mm | 24”H x 32”W x 32”D (609.6 x 812.8 x 812.8 mm) |
| Weight | 48 kg | 115.1 lbs (52.2 kg) |
| XLR Input | Yes | - |
| AES Input | Yes | - |
| Country | Finland | United States |
| Enclosure | - | ported, front |
| Passive | - | Yes |
| Output SPL at 12.5 Hz | - | 96.2 dB |
| Output SPL at 15 Hz | - | 111.9 dB |
| Output SPL at 20 Hz | - | 121.9 dB |
| Output SPL at 25 Hz | - | 120.8 dB |
| Output SPL at 31.5 Hz | - | 122.5 dB |
| Output SPL at 40 Hz | - | 126.7 dB |
| Output SPL at 50 Hz | - | 129.2 dB |
| Output SPL at 63 Hz | - | 132.9 dB |
| Output SPL at 80 Hz | - | 136.3 dB |
| Output SPL at 100 Hz | - | 139.0 dB |
| Output SPL at 125 Hz | - | 140.1 dB |
| CEA-2010-A Average (40-80Hz) | - | 131.3 dB |
| Measurement Source | - | Data-bass |
Prices on this page were last checked September 29, 2026 at 3:43 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
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The Two Speakers In Full
Genelec 7370A: $4,195 B&H Photo Video eBay
Older model: the Genelec 7070A (rated 3.6/5).
Pros: 12-inch (305mm) driver with a 400W Class D amplifier. Genelec rates it at 19-100Hz within 3dB and at least 113dB short-term maximum output. Analog and AES/EBU digital XLR inputs and outputs, and GLM network control with AutoCal 2 room calibration.
Cons: No independent measurements yet, so its output can’t be compared with ranked subwoofers. Room calibration needs Genelec’s GLM kit or 9320A controller, sold separately, and at 48kg it is heavy for its size.
Full Genelec 7370A review and specifications →
| AES Input | Yes |
|---|---|
| Amplifier Power | 400W (Class D) |
| Country | Finland |
| Dimensions | 625H x 555W x 496D mm |
| Drivers | 12” (305mm) driver |
| Frequency Response | 19Hz - 100Hz (+/-3dB) (Manufacturer specified) |
| Maximum SPL | 113 dB |
| Weight | 48 kg |
| XLR Input | Yes |
- Links
- Reviews, Comparisons and Sound Samples
- These figures are manufacturer-specified rather than independently measured.
- Head-to-Head Comparisons
WW Speaker Cabinets X21 - B&C 21DS115-4: $3995 Passive eBay
Pros: 21-inch driver in a large ported cabinet delivers 131.3dB CEA-2010-A average, the highest output of any passive subwoofer tested.
Cons: Premium $3995 price, massive 52 kg cabinet, and ported room gain dependency.
Full WW Speaker Cabinets X21 - B&C 21DS115-4 review and specifications →
| CEA-2010-A Average (40-80Hz) | 131.3 dB |
|---|---|
| Country | United States |
| Dimensions | 24”H x 32”W x 32”D (609.6 x 812.8 x 812.8 mm) |
| Drivers | 21” (533mm) driver |
| Enclosure | ported, front |
| Measurement Source | Data-bass |
| Output SPL at 12.5 Hz | 96.2 dB |
| Output SPL at 15 Hz | 111.9 dB |
| Output SPL at 20 Hz | 121.9 dB |
| Output SPL at 25 Hz | 120.8 dB |
| Output SPL at 31.5 Hz | 122.5 dB |
| Output SPL at 40 Hz | 126.7 dB |
| Output SPL at 50 Hz | 129.2 dB |
| Output SPL at 63 Hz | 132.9 dB |
| Output SPL at 80 Hz | 136.3 dB |
| Output SPL at 100 Hz | 139.0 dB |
| Output SPL at 125 Hz | 140.1 dB |
| Passive | Yes |
| Weight | 115.1 lbs (52.2 kg) |
- Reviews, Comparisons and Sound Samples
- Independently measured by Data-bass; the published figures above come from this ASR subwoofer measurement thread.
- Head-to-Head Comparisons
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs Pro Audio Technology LFC-24sm
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs JTR Speakers Captivator S2
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs JTR Speakers Growler (2015)
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs Danley Sound Labs DTS10
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs Monoprice Monolith 16 THX Ultra
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs Reaction Audio PV-15X
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs JBL 4645C
- WW Speaker Cabinets X21 - B&C 21DS115-4 vs Chase Home Theater SS18.1
- See all 10 comparisons